diff --git a/include/os/linux/spl/sys/debug.h b/include/os/linux/spl/sys/debug.h
index 81ef2ca0ea91..172e2b9b2239 100644
--- a/include/os/linux/spl/sys/debug.h
+++ b/include/os/linux/spl/sys/debug.h
@@ -105,6 +105,7 @@ spl_assert(const char *buf, const char *file, const char *func, int line)
 
 #ifdef NDEBUG
 #define	VERIFY(cond) (void) ((!(cond)))
+#define	VERIFYF(cond) do { } while(0)
 
 #define	VERIFY3B(LEFT, OP, RIGHT)					\
 do {									\
diff --git a/lib/libspl/include/assert.h b/lib/libspl/include/assert.h
index 27505295a3eb..b2b768b88838 100644
--- a/lib/libspl/include/assert.h
+++ b/lib/libspl/include/assert.h
@@ -63,77 +63,173 @@ libspl_assert(const char *buf, const char *file, const char *func, int line)
 #ifdef verify
 #undef verify
 #endif
+
 #ifdef NDEBUG
 #define	VERIFY(cond) (void) ((!(cond)))
+#define	VERIFYF(cond, STR, ...) do { } while(0)
 #define	verify(cond) (void) ((!(cond)))
 
 #define	PANIC(fmt, a...)						\
-	libspl_assertf(__FILE__, __FUNCTION__, __LINE__, fmt, ## a)
+	libspl_assertf("unknown", __FUNCTION__, __LINE__, fmt, ## a)
 
 #define	VERIFY3B(LEFT, OP, RIGHT)					\
 do {									\
-	const boolean_t __left __attribute__((unused)) = \
-		(boolean_t)(LEFT);	\
-	const boolean_t __right __attribute__((unused)) = \
-		(boolean_t)(RIGHT);	\
+	const boolean_t __left = (boolean_t)(LEFT);			\
+	const boolean_t __right = (boolean_t)(RIGHT);			\
+	if (!(__left OP __right))					\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s %s %s (0x%llx %s 0x%llx)", #LEFT, #OP, #RIGHT,	\
+		    (u_longlong_t)__left, #OP, (u_longlong_t)__right);	\
 } while (0)
 
 #define	VERIFY3S(LEFT, OP, RIGHT)					\
 do {									\
-	const int64_t __left __attribute__((unused)) = \
-		(int64_t)(LEFT);		\
-	const int64_t __right __attribute__((unused)) = \
-		(int64_t)(RIGHT);	\
+	const int64_t __left = (int64_t)(LEFT);				\
+	const int64_t __right = (int64_t)(RIGHT);			\
+	if (!(__left OP __right))					\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s %s %s (0x%llx %s 0x%llx)", #LEFT, #OP, #RIGHT,	\
+		    (u_longlong_t)__left, #OP, (u_longlong_t)__right);	\
 } while (0)
 
 #define	VERIFY3U(LEFT, OP, RIGHT)					\
 do {									\
-	const uint64_t __left __attribute__((unused)) = \
-		(uint64_t)(LEFT);	\
-	const uint64_t __right __attribute__((unused)) = \
-		(uint64_t)(RIGHT);	\
+	const uint64_t __left = (uint64_t)(LEFT);			\
+	const uint64_t __right = (uint64_t)(RIGHT);			\
+	if (!(__left OP __right))					\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s %s %s (0x%llx %s 0x%llx)", #LEFT, #OP, #RIGHT,	\
+		    (u_longlong_t)__left, #OP, (u_longlong_t)__right);	\
 } while (0)
 
 #define	VERIFY3P(LEFT, OP, RIGHT)					\
 do {									\
-	const uintptr_t __left __attribute__((unused)) = \
-		(uintptr_t)(LEFT);	\
-	const uintptr_t __right __attribute__((unused)) = \
-		(uintptr_t)(RIGHT);	\
+	const uintptr_t __left = (uintptr_t)(LEFT);			\
+	const uintptr_t __right = (uintptr_t)(RIGHT);			\
+	if (!(__left OP __right))					\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s %s %s (%p %s %p)", #LEFT, #OP, #RIGHT,		\
+		    (void *)__left, #OP, (void *)__right);		\
 } while (0)
 
 #define	VERIFY0(LEFT)							\
 do {									\
-	const uint64_t __left __attribute__((unused)) = \
-		(uint64_t)(LEFT);	\
+	const uint64_t __left = (uint64_t)(LEFT);			\
+	if (!(__left == 0))						\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s == 0 (0x%llx == 0)", #LEFT,			\
+		    (u_longlong_t)__left);				\
+} while (0)
+
+#define	VERIFY0P(LEFT)							\
+do {									\
+	const uintptr_t __left = (uintptr_t)(LEFT);			\
+	if (!(__left == 0))						\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s == 0 (%p == 0)", #LEFT,				\
+		    (void *)__left);					\
+} while (0)
+
+/*
+ * This is just here because cstyle gets upset about #LEFT
+ * on a newline.
+ */
+
+/* BEGIN CSTYLED */
+#define	VERIFY3BF(LEFT, OP, RIGHT, STR, ...)				\
+do {									\
+	const boolean_t __left = (boolean_t)(LEFT);			\
+	const boolean_t __right = (boolean_t)(RIGHT);			\
+	if (!(__left OP __right))					\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s %s %s (0x%llx %s 0x%llx) " STR,			\
+		    #LEFT, #OP, #RIGHT,					\
+		    (u_longlong_t)__left, #OP, (u_longlong_t)__right,	\
+		    __VA_ARGS__);					\
+} while (0)
+
+#define	VERIFY3SF(LEFT, OP, RIGHT, STR, ...)				\
+do {									\
+	const int64_t __left = (int64_t)(LEFT);				\
+	const int64_t __right = (int64_t)(RIGHT);			\
+	if (!(__left OP __right))					\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s %s %s (0x%llx %s 0x%llx) " STR,			\
+		    #LEFT, #OP, #RIGHT,					\
+		    (u_longlong_t)__left, #OP, (u_longlong_t)__right,	\
+		    __VA_ARGS__);					\
+} while (0)
+
+#define	VERIFY3UF(LEFT, OP, RIGHT, STR, ...)				\
+do {									\
+	const uint64_t __left = (uint64_t)(LEFT);			\
+	const uint64_t __right = (uint64_t)(RIGHT);			\
+	if (!(__left OP __right))					\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s %s %s (0x%llx %s 0x%llx) " STR,			\
+		    #LEFT, #OP, #RIGHT,					\
+		    (u_longlong_t)__left, #OP, (u_longlong_t)__right,	\
+		    __VA_ARGS__);					\
+} while (0)
+
+#define	VERIFY3PF(LEFT, OP, RIGHT, STR, ...)				\
+do {									\
+	const uintptr_t __left = (uintptr_t)(LEFT);			\
+	const uintptr_t __right = (uintptr_t)(RIGHT);			\
+	if (!(__left OP __right))					\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s %s %s (0x%llx %s 0x%llx) " STR,			\
+		    #LEFT, #OP, #RIGHT,					\
+		    (u_longlong_t)__left, #OP, (u_longlong_t)__right,	\
+		    __VA_ARGS__);					\
 } while (0)
+/* END CSTYLED */
+
+#define	VERIFY0F(LEFT, STR, ...)					\
+do {									\
+	const uint64_t __left = (uint64_t)(LEFT);			\
+	if (!(__left == 0))						\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s == 0 (0x%llx == 0) " STR, #LEFT,		\
+		    (u_longlong_t)__left, __VA_ARGS__);			\
+} while (0)
+
+#define	VERIFY0PF(LEFT, STR, ...)					\
+do {									\
+	const uintptr_t __left = (uintptr_t)(LEFT);			\
+	if (!(__left == 0))						\
+		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		    "%s == 0 (%p == 0) " STR, #LEFT,			\
+		    (u_longlong_t)__left, __VA_ARGS__);			\
+} while (0)
+
 #else
 
+#define	PANIC(fmt, a...)						\
+	libspl_assertf(__FILE__, __FUNCTION__, __LINE__, fmt, ## a)
+
 #define	VERIFY(cond)							\
 	(void) ((!(cond)) &&						\
-	    libspl_assert(#cond, "unknown", __FUNCTION__, __LINE__))
+	    libspl_assert(#cond, __FILE__, __FUNCTION__, __LINE__))
 
 #define	VERIFYF(cond, STR, ...)						\
 do {									\
 	if (!(cond))							\
-		libspl_assertf( "unknown", __FUNCTION__, __LINE__,	\
+		libspl_assertf(__FILE__, __FUNCTION__, __LINE__,	\
 		    "%s " STR, #cond,					\
 		    __VA_ARGS__);					\
 } while (0)
 
 #define	verify(cond)							\
 	(void) ((!(cond)) &&						\
-	    libspl_assert(#cond, "unknown", __FUNCTION__, __LINE__))
-
-#define	PANIC(fmt, a...)						\
-	libspl_assertf("unknown", __FUNCTION__, __LINE__, fmt, ## a)
+	    libspl_assert(#cond, __FILE__, __FUNCTION__, __LINE__))
 
 #define	VERIFY3B(LEFT, OP, RIGHT)					\
 do {									\
 	const boolean_t __left = (boolean_t)(LEFT);			\
 	const boolean_t __right = (boolean_t)(RIGHT);			\
 	if (!(__left OP __right))					\
-		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		libspl_assertf(__FILE__, __FUNCTION__, __LINE__,	\
 		    "%s %s %s (0x%llx %s 0x%llx)", #LEFT, #OP, #RIGHT,	\
 		    (u_longlong_t)__left, #OP, (u_longlong_t)__right);	\
 } while (0)
@@ -143,7 +239,7 @@ do {									\
 	const int64_t __left = (int64_t)(LEFT);				\
 	const int64_t __right = (int64_t)(RIGHT);			\
 	if (!(__left OP __right))					\
-		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		libspl_assertf(__FILE__, __FUNCTION__, __LINE__,	\
 		    "%s %s %s (0x%llx %s 0x%llx)", #LEFT, #OP, #RIGHT,	\
 		    (u_longlong_t)__left, #OP, (u_longlong_t)__right);	\
 } while (0)
@@ -153,7 +249,7 @@ do {									\
 	const uint64_t __left = (uint64_t)(LEFT);			\
 	const uint64_t __right = (uint64_t)(RIGHT);			\
 	if (!(__left OP __right))					\
-		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		libspl_assertf(__FILE__, __FUNCTION__, __LINE__,	\
 		    "%s %s %s (0x%llx %s 0x%llx)", #LEFT, #OP, #RIGHT,	\
 		    (u_longlong_t)__left, #OP, (u_longlong_t)__right);	\
 } while (0)
@@ -163,7 +259,7 @@ do {									\
 	const uintptr_t __left = (uintptr_t)(LEFT);			\
 	const uintptr_t __right = (uintptr_t)(RIGHT);			\
 	if (!(__left OP __right))					\
-		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		libspl_assertf(__FILE__, __FUNCTION__, __LINE__,	\
 		    "%s %s %s (%p %s %p)", #LEFT, #OP, #RIGHT,		\
 		    (void *)__left, #OP, (void *)__right);		\
 } while (0)
@@ -172,7 +268,7 @@ do {									\
 do {									\
 	const uint64_t __left = (uint64_t)(LEFT);			\
 	if (!(__left == 0))						\
-		libspl_assertf("unknown", __FUNCTION__, __LINE__,	\
+		libspl_assertf(__FILE__, __FUNCTION__, __LINE__,	\
 		    "%s == 0 (0x%llx == 0)", #LEFT,			\
 		    (u_longlong_t)__left);				\
 } while (0)
@@ -258,8 +354,8 @@ do {									\
 		    "%s == 0 (%p == 0) " STR, #LEFT,			\
 		    (u_longlong_t)__left, __VA_ARGS__);			\
 } while (0)
-#endif
 
+#endif
 #ifdef assert
 #undef assert
 #endif
@@ -308,11 +404,11 @@ do {									\
 #define	IMPLY(A, B) \
 	((void)(((!(A)) || (B)) || \
 	    libspl_assert("(" #A ") implies (" #B ")", \
-	    "unknown", __FUNCTION__, __LINE__)))
+	    __FILE__, __FUNCTION__, __LINE__)))
 #define	EQUIV(A, B) \
 	((void)((!!(A) == !!(B)) || \
 	    libspl_assert("(" #A ") is equivalent to (" #B ")", \
-	    "unknown", __FUNCTION__, __LINE__)))
+	    __FILE__, __FUNCTION__, __LINE__)))
 
 #endif  /* NDEBUG */